Ingestible Origami Robot Crawls Across Stomach to Patch Wounds
To address the serious problems associated with children swallowing button batteries, researchers at MIT, the University of Sheffield, and the Tokyo Institute of Technology have demonstrated a tiny origami robot that can unfold itself from a swallowed capsule and, steered by external magnetic fields, crawl across the stomach wall to remove a swallowed button battery or patch a wound. It can propel itself using what's called a 'stick-slip' motion, in which its appendages stick to a surface through friction when it executes a move, but slip free again when its body flexes to change its weight distribution. The robot consists of two layers of structural material sandwiching a material that shrinks when heated. A pattern of slits in the outer layers determines how the robot will fold when the middle layer contracts.